Three gases (8.00 g of methane, CH_{4}, 18.0 g of ethane, C_{2}H_{6}, and an unknown amount of propane, C_{3}H_{8}) were added to the same 10.0-L container. At 23.0 °C, the total pressure in the container is 4.50 atm. Calculate the partial pressure of each gas in the container.

Express the pressure values numerically in atmospheres, separated by commas. Enter the partial pressure of methane first, then ethane, then propane.

Dalton's law states that the total pressure, *P*_{total}, of a mixture of gases in a container equals the sum of the pressures of each individual gas:

${\mathbf{P}}_{\mathbf{total}}\mathbf{=}{\mathbf{P}}_{\mathbf{1}}\mathbf{+}{\mathbf{P}}_{\mathbf{2}}\mathbf{+}{\mathbf{P}}_{\mathbf{3}}\mathbf{+}\mathbf{.}\mathbf{.}\mathbf{.}$

The *partial pressure* of the first component, *P*_{1}, is equal to the mole fraction of this component, *X*_{1}, times the total pressure of the mixture:

${\mathbf{P}}_{\mathbf{1}}\mathbf{=}{\mathbf{X}}_{\mathbf{1}}\mathbf{\times}{\mathbf{P}}_{\mathbf{total}}$

The *mole fraction*, *X*, represents the concentration of the component in the gas mixture, so

${\mathbf{X}}_{\mathbf{1}}\mathbf{=}\frac{\mathbf{moles}\mathbf{}\mathbf{of}\mathbf{}\mathbf{component}\mathbf{}\mathbf{1}}{\mathbf{total}\mathbf{}\mathbf{moles}\mathbf{}\mathbf{in}\mathbf{}\mathbf{mixture}}$

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